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Your search keyword '"Xu, M. H."' showing total 113 results
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113 results on '"Xu, M. H."'

1. The Potsdam Open Source Radio Interferometry Tool (PORT)

Author

Schuh, H., Heinkelmann, R., Beyerle, G., Anderson, J. M., Balidakis, K., Belda, S., Dhar, S., Glaser, S., Jenie, O. S., Karbon, M., Kitpracha, C., Nehbit, P. Küreç, Liu, L., Lunz, S., Mammadaliyev, N., Modiri, S., Nilsson, T. J., Raut, S., Soja, B., Wang, J., and Xu, M. H.

Published
2021

2. Cross‐Polarization Gain Calibration of Linearly Polarized VLBI Antennas by Observations of 4C 39.25.

Author

Jaron, F., Martí‐Vidal, I., Schartner, M., González‐García, J., Albentosa‐Ruiz, E., Bernhart, S., Böhm, J., Gruber, J., Modiri, S., Nothnagel, A., Pérez‐Díez, V., Savolainen, T., Soja, B., Varenius, E., and Xu, M. H.

Subjects
ANTENNAS (Electronics), VERY long baseline interferometry, RADIO telescopes, LINEAR polarization, SIGNAL-to-noise ratio
Abstract

Radio telescopes with dual linearly polarized feeds regularly participate in Very Long Baseline Interferometry. One example is the VLBI Global Observing System (VGOS), which is employed for high‐precision geodesy and astrometry. In order to achieve the maximum signal‐to‐noise ratio, the visibilities of all four polarization products are combined to Stokes I before fringe‐fitting. Our aim is to improve cross‐polarization bandpass calibration, which is an essential processing step in this context. Here we investigate the shapes of these station‐specific quantities as a function of frequency and time. We observed the extra‐galactic source 4C 39.25 for 6 hours with a VGOS network. We correlated the data with the DiFX software and analyzed the visibilities with PolConvert to determine the complex cross‐bandpasses with high accuracy. Their frequency‐dependent shape is to first order characterized by a group delay between the two orthogonal polarizations, in the order of several hundred picoseconds. We find that this group delay shows systematic variability in the range of a few picoseconds, but can remain stable within this range for several years, as evident from earlier sessions. On top of the linear phase‐frequency relationship there are systematic deviations of several tens of degrees, which in addition are subject to smooth temporal evolution. The antenna cross‐bandpasses are variable on time scales of ∼1 hr, which defines the frequency of necessary calibrator scans. The source 4C 39.25 is confirmed as an excellent cross‐bandpass calibrator. Dedicated surveys are highly encouraged to search for more calibrators of similar quality. Key Points: The new‐generation geodetic radio telescopes observe two orthogonal linear polarization directionsCalibration of the gain differences between the two polarizers is necessary to maximize the signal‐to‐noise ratio of observationsWe investigate these cross‐polarization gain differences and their temporal evolution for selected antennas [ABSTRACT FROM AUTHOR]

Published
2024
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4. High Energy Physics Opportunities Using Reactor Antineutrinos

Author

Awe, C., Barbeau, P. S., Haghighat, A., Huber, P., Li, S. C., Link, J. M., Mascolino, V., Subedi, T., Walkup, K., Aguilar-Arevalo, A., Bertou, X., Bonifazi, C., Cancelo, G., Cervantes-Vergara, B. A., Chavez, C., D Olivo, J. C., Egea, J. M., Dos Anjos, J. C., Estrada, J., Neto, A. R. F., Fernandez-Moroni, G., Foguel, A., Ford, R., Gasanego, J., Gollo, V., Izraelevitch, F., Kilminster, B., Lima, Jr H. P., Makler, M., Mendes, L. H., Molina, J., Mota, P., Nasteva, I., Paolini, E., Romero, C., Sarkis, Y., Haro, M. S., Soto, A., Stalder, D., Tiffenberg, J., Torres, C., Lindner, M., An, F. P., Balantekin, A. B., Band, H. R., Bishai, M., Blyth, S., Cao, G. F., Cao, J., Chang, J. F., Chang, Y., Chen, H. S., Chen, S. M., Chen, Y., Chen, Y. X., Cheng, J., Cheng, Z. K., Cherwinka, J. J., Chu, M. C., Cummings, J. P., Dalager, O., Deng, F. S., Ding, Y. Y., Diwan, M. V., Dohnal, T., Dove, J., Dvořák, M., Dwyer, D. A., Gallo, J. P., Gonchar, M., Gong, G. H., Gong, H., Gu, W. Q., Guo, J. Y., Guo, L., Guo, X. H., Guo, Y. H., Guo, Z., Hackenburg, R. W., Hans, S., He, M., Heeger, K. M., Heng, Y. K., Higuera, A., Hor, Y. K., Hsiung, Y. B., Hu, B. Z., Hu, J. R., Hu, T., Hu, Z. J., Huang, H. X., Huang, X. T., Jaffe, D. E., Jen, K. L., Ji, X. L., Ji, X. P., Johnson, R. A., Jones, D., Kang, L., Kettell, S. H., Kohn, S., Kramer, M., Langford, T. J., Lee, J., Lee, J. H. C., Lei, R. T., Leitner, R., Leung, J. K. C., Li, F., Li, H. L., Li, J. J., Li, Q. J., Li, S., Li, W. D., Li, X. N., Li, X. Q., Li, Y. F., Li, Z. B., Liang, H., Lin, C. J., Lin, G. L., Lin, S., Ling, J. J., Littenberg, L., Littlejohn, B. R., Liu, J. C., Liu, J. L., Lu, C., Lu, H. Q., Lu, J. S., Luk, K. B., Ma, X. B., Ma, X. Y., Ma, Y. Q., Mandujano, R. C., Marshall, C., Martinez Caicedo, D. A., Mcdonald, K. T., Mckeown, R. D., Meng, Y., Napolitano, J., Naumov, D., Naumova, E., Ochoa-Ricoux, J. P., Olshevskiy, A., Pan, H. -R, Park, J., Patton, S., Peng, J. C., Pun, C. S. J., Qi, F. Z., Qi, M., Qian, X., Raper, N., Ren, J., Reveco, C. Morales, Rosero, R., Roskovec, B., Ruan, X. C., Steiner, H., Sun, J. L., Tmej, T., Treskov, K., Tse, W. -H, Tull, C. E., Viren, B., Vorobel, V., Wang, C. H., Wang, J., Wang, M., Wang, N. Y., Wang, R. G., Wang, W., Wang, X., Wang, Y., Wang, Y. F., Wang, Z., Wang, Z. M., Wei, H. Y., Wei, L. H., Wen, L. J., Whisnant, K., White, C. G., Wong, H. L. H., Worcester, E., Wu, D. R., Wu, F. L., Wu, Q., Wenjie Wu, Xia, D. M., Xie, Z. Q., Xing, Z. Z., Xu, J. L., Xu, T., Xue, T., Yang, C. G., Yang, L., Yang, Y. Z., Yao, H. F., Ye, M., Yeh, M., Young, B. L., Yu, H. Z., Yu, Z. Y., Yue, B. B., Zeng, S., Zeng, Y., Zhan, L., Zhang, C., Zhang, F. Y., Zhang, H. H., Zhang, J. W., Zhang, Q. M., Zhang, X. T., Zhang, Y. M., Zhang, Y. X., Zhang, Y. Y., Zhang, Z. J., Zhang, Z. P., Zhang, Z. Y., Zhao, J., Zhou, L., Zhuang, H. L., Zou, J. H., Abusleme, A., Adam, T., Ahmad, S., Ahmed, R., Aiello, S., An, G. P., An, Q., Andronico, G., Anfimov, N., Antonelli, V., Antoshkina, T., Asavapibhop, B., André, J. P. A. M., Auguste, D., Babic, A., Baldini, W., Barresi, A., Baussan, E., Bellato, M., Bergnoli, A., Bernieri, E., Birkenfeld, T., Blin, S., Blum, D., Bolshakova, A., Bongrand, M., Bordereau, C., Breton, D., Brigatti, A., Brugnera, R., Bruno, R., Budano, A., Buesken, M., Buscemi, M., Busto, Jose, Butorov, I., Cabrera, A., Cai, H., Cai, X., Cai, Y. K., Cai, Z. Y., Cammi, A., Campeny, A., Cao, C. Y., Caruso, R., Cerna, C., Chakaberia, I., Chen, P. P., Chen, P. A., Chen, S., Chen, X., Chen, Y. W., Chen, Z., Cheng, Y., Chiesa, D., Chimenti, P., Chukanov, A., Chuvashova, A., Claverie, G., Clementi, C., Clerbaux, B., Di Lorenzo, S., Corti, D., Costa, S., Corso, F. D., La Taille, C., Deng, J., Deng, Z., Deng, Z. Y., Depnering, W., Diaz, M., Ding, X. F., Dirgantara, B., Dmitrievsky, S., Donchenko, G., Dong, J. M., Dornic, D., Doroshkevich, E., Dracos, M., Druillole, F., Du, S. X., Dusini, S., Dvorak, M., Enqvist, T., Enzmann, H., Fabbri, A., Fajt, L., Fan, D. H., Fan, L., Fang, C., Fang, J., Fang, W. X., Fargetta, M., Fatkina, A., Fedoseev, D., Fekete, V., Feng, L. C., Feng, Q. C., Formozov, A., Fournier, A., Gan, H. N., Gao, F., Garfagnini, A., Göttel, A., Genster, C., Giammarchi, M., Giaz, A., Giudice, N., Gong, G., Gorchakov, O., Gornushkin, Y., Grassi, M., Grewing, C., Gromov, V., Gu, M., Gu, X., Gu, Y., Guan, M. Y., Guardone, N., Gul, M., Guo, C., Guo, W. L., Hackspacher, P., Hagner, C., Han, R., Han, Y., Hassan, M., He, W., Heinz, T., Hellmuth, P., Herrera, R., Hong, D. J., Hou, S. J., Hsiung, Y., Hu, H., Hu, J., Hu, S. Y., Huang, C. H., Huang, G. H., Huang, Q. H., Huang, W. H., Huang, X., Huang, Y. B., Hui, J. Q., Huo, L., Huo, W., Huss, C., Hussain, S., Insolia, A., Ioannisian, A., Isocrate, R., Ji, X. Z., Jia, H. H., Jia, J. J., Jian, S. Y., Jiang, D., Jiang, X. S., Jin, R. Y., Jing, X. P., Jollet, C., Joutsenvaara, J., Jungthawan, S., Kalousis, L., Kampmann, P., Karagounis, M., Kazarian, N., Khan, A., Khan, W., Khosonthongkee, K., Kinz, P., Korablev, D., Kouzakov, K., Krasnoperov, A., Krumshteyn, Z., Kruth, A., Kutovskiy, N., Kuusiniemi, P., Lachenmaier, T., Landini, C., Leblanc, S., Lebrin, V., Lefevre, F., Lei, R., Leung, J., Li, C., Li, D., Li, H., Li, J., Li, K. J., Li, M. Z., Li, M., Li, N., Li, R. H., Li, S. F., Li, S. J., Li, T., Li, W. G., Li, X. M., Li, X. L., Li, Y., Li, Z., Li, Z. Y., Liang, J. J., Liebau, D., Limphirat, A., Limpijumnong, S., Lin, S. X., Lin, T., Lippi, I., Liu, F., Liu, H. D., Liu, H. B., Liu, H. J., Liu, H. T., Liu, H., Liu, M., Liu, Q., Liu, R. X., Liu, S. Y., Liu, S. B., Liu, S. L., Liu, X. W., Liu, X., Liu, Y., Lokhov, A., Lombardi, P., Lombardo, C., Loo, K., Lu, J. B., Lu, J. G., Lu, S. X., Lu, X. X., Lubsandorzhiev, B., Lubsandorzhiev, S., Ludhova, L., Luo, F. J., Luo, G., Luo, P. W., Luo, S., Luo, W. M., Lyashuk, V., Ma, Q. M., Ma, S., Maalmi, J., Malyshkin, Y., Mantovani, F., Manzali, F., Mao, X., Mao, Y. J., Mari, S. M., Marini, F., Marium, S., Martellini, C., Martin-Chassard, G., Martini, A., Mayilyan, D., Müller, A., Mednieks, I., Meregaglia, A., Meroni, E., Meyhöfer, D., Mezzetto, M., Miller, J., Miramonti, L., Monforte, S., Montini, P., Montuschi, M., Morozov, N., Muhammad, A., Muralidharan, P., Nastasi, M., Naumov, D. V., Nemchenok, I., Ning, F. P., Ning, Z., Nunokawa, H., Oberauer, L., Orestano, D., Ortica, F., Pan, H. R., Paoloni, A., Parkalian, N., Parmeggiano, S., Payupol, T., Pei, Y., Pelliccia, N., Peng, A., Peng, H., Perrot, F., Petitjean, P. A., Petrucci, F., Piñeres Rico, L. F., Pilarczyk, O., Popov, A., Poussot, P., Pratumwan, W., Previtali, E., Qi, F., Qian, S., Qian, X. H., Qiao, H., Qin, Z. H., Qiu, S. K., Rajput, M., Ranucci, G., Re, A., Rebber, H., Rebii, A., Ren, B., Rezinko, T., Ricci, B., Robens, M., Roche, M., Rodphai, N., Romani, A., Roth, C., Ruan, X., Rujirawat, S., Rybnikov, A., Sadovsky, A., Saggese, P., Salamanna, G., Sanfilippo, S., Sangka, A., Sanguansak, N., Sawangwit, U., Sawatzki, J., Sawy, F., Schever, M., Schuler, J., Schwab, C., Schweizer, K., Selivanov, D., Selyunin, A., Serafini, A., Settanta, G., Settimo, M., Shao, Z., Sharov, V., Shi, J., Shutov, V., Sidorenkov, A., Simkovic, F., Sirignano, C., Siripak, J., Sisti, M., Slupecki, M., Smirnov, M., Smirnov, O., Sogo-Bezerra, T., Songwadhana, J., Soonthornthum, B., Sotnikov, A., Sramek, O., Sreethawong, W., Stahl, A., Stanco, L., Stankevich, K., Stefanik, D., Steiger, H., Steinmann, J., Sterr, T., Stock, M. R., Strati, V., Studenikin, A., Sun, G. X., Sun, S. F., Sun, X. L., Sun, Y. J., Sun, Y. Z., Suwonjandee, N., Szelezniak, M., Tang, J., Tang, Q., Tang, X., Tietzsch, A., Tkachev, I., Triossi, A., Troni, G., Trzaska, W., Tuve, C., Ushakov, N., Waasen, S., Boom, J. Vanden, Vanroyen, G., Vassilopoulos, N., Vedin, V., Verde, G., Vialkov, M., Viaud, B., Volpe, C., Voronin, D., Votano, L., Walker, P., Wang, C., Wang, E., Wang, G., Wang, K. Y., Wang, L., Wang, M. F., Wang, S. G., Wang, W. S., Wang, X. Y., Wang, Y. G., Wang, Y. Q., Wang, Z. Y., Waqas, M., Watcharangkool, A., Wei, W., Wei, Y. D., Wiebusch, C., Wong, S. C. F., Wonsak, B., Wu, D., Wu, W. J., Wu, Z., Wurm, M., Wurtz, J., Wysotzki, C., Xi, Y. F., Xie, Y. G., Xu, B., Xu, C., Xu, D. L., Xu, F. R., Xu, H. K., Xu, J., Xu, M. H., Xu, Y., Yan, B. J., Yan, T., Yan, W. Q., Yan, X. B., Yan, Y. P., Yang, A. B., Yang, H., Yang, J., Yang, X. Y., Yang, Y., Yang, Y. F., Yasin, Z., Ye, J. X., Ye, Z. P., Yegin, U., Yermia, F., Yi, P. H., Yin, X. W., You, Z. Y., Yu, B. X., Yu, C. Y., Yu, C. X., Yu, M., Yu, X. H., Yuan, C. Z., Yuan, Y., Yuan, Z. X., Yuan, Z. Y., Zafar, N., Zambanini, A., Zeng, T. X., Zeng, Y. D., Zhang, G. Q., Zhang, H. Q., Zhang, J., Zhang, J. B., Zhang, P., Zhang, S., Zhang, T., Zhang, X. M., Zhang, Y., Zhang, Y. H., Zhang, Y. P., Zhao, F. Y., Zhao, R., Zhao, S. J., Zhao, T. C., Zheng, D. Q., Zheng, H., Zheng, M. S., Zheng, Y. H., Zhong, W. R., Zhou, J., Zhou, N., Zhou, S., Zhou, X., Zhu, J., Zhu, K. J., Zhuang, B., Zong, L., Rasco, B. C., Han, B. Y., Jeon, E. J., Jeong, Y., Jo, H. S., Kim, D. K., Kim, J. Y., Kim, J. G., Kim, Y. D., Ko, Y. J., Lee, H. M., Lee, M. H., Moon, C. S., Oh, Y. M., Park, H. K., Park, K. S., Seo, S. H., Siyeon, K., Sun, G. M., Yoon, Y. S., Yu, I., Borusinski, M. J., Dorrill, R., Druetzler, A., Learned, J., Li, V., Markoff, D., Maricic, J., Matsuno, S., Mumm, H. P., Nishimura, K., Irani, A., Pitt, M., Rasco, C., Thibodeau, B., Varner, G., Vogelaar, B., Wright, T., Andriamirado, M., Bass, C. D., Bergeron, D. E., Berish, D., Bowden, N. S., Brodsky, J. P., Bryan, C. D., Carr, R., Classen, T., Conant, A. J., Deichert, G., Dolinski, M. J., Erickson, A., Foust, B. T., Gaison, J. K., Galindo-Uribarri, A., Gilbert, C. E., Grant, C., Hackett, B. T., Hansell, A. B., Ji, X., Jones, D. C., Kyzylova, O., Lane, C. E., Larosa, J., Lu, X., Mendenhall, M. P., Meyer, A. M., Milincic, R., Mitchell, I., Mueller, P. E., Nave, C., Neilson, R., Nikkel, J. A., Norcini, D., Nour, S., Palomino, J. L., Pushin, D. A., Romero-Romero, E., Surukuchi, P. T., Tyra, M. A., Varner, R. L., Venegas-Vargas, D., Weatherly, P. B., White, C., Wilhelmi, J., Woolverton, A., Zhang, A., Zhang, X., Choi, J. H., Jang, H. I., Jang, J. S., Jeon, S. H., Joo, K. K., Ju, K., Jung, D. E., Kim, J. H., Kim, S. B., Kim, S. Y., Kim, W., Kwon, E., Lee, D. H., Lee, H. G., Lim, I. T., Moon, D. H., Pac, M. Y., Seo, H., Seo, J. W., Shin, C. D., Yang, B. S., Yoo, J., Yoon, S. G., Yeo, I. S., Chang, C., Bergé, L., Broniatowski, A., Dumoulin, L., Giuliani, A., Chapellier, M., Marcillac, P., Marnieros, S., Olivieri, E., Poda, D., Calvo, M., Goupy, J., Monfardini, A., Arnaud, Q., Augier, C., Billard, J., Cazes, A., Colas, J., Filippini, J., Gascon, J., Jesus, M., Lattaud, H., Juillard, A., Salagnac, T., Soldner, T., Lubashevskiy, A., Yakushev, E., Rozov, S., Lamblin, J., Mom, B., Stutz, A., Formaggio, J. A., Mayer, D. W., Johnston, J., Harrington, P., Heine, S., Sibille, V., Chen, R., Figueroa-Feliciano, E., Ziqing, H., Hertel, S., Patel, P., Pinckney, D., Serafin, A., Shilcusky, A., Decheine, N., Palladino, K., Weber, S., Hirjibehedin, C., Akindele, O. A., Carman, L., Dazeley, S., Ford, M., Jovanovic, I., Sutanto, F., Zaitseva, N., Beaumont, W., Binet, S., Bolognino, I., Borg, J., Buridon, V., Chanal, H., Coupé, B., Crochet, P., Cussans, D., Roeck, A., Durand, D., Fallot, M., Galbinski, D., Gallego, S., Giot, L., Guillon, B., Henaff, D., Hayashida, S., Hosseini, B., Kalcheva, S., Lehaut, G., Michiels, I., Monteil, S., Newbold, D., Roy, N., Ryckbosch, D., Sfar, H. Rejeb, Simard, L., Vacheret, A., Vandierendonck, G., Dyck, S., Remortel, N., Vercaemer, S., Verstraeten, M., Weber, A., Yeresko, M., Bonhomme, A., Buck, C., Del Amo Sanchez, P., El Atmani, I., Labit, L., Letourneau, A., Lhuillier, D., Licciardi, M., Materna, T., Pessard, H., Rogly, R., Savu, V., Schoppmann, S., Vialat, M., Algora, A., Beloeuvre, A., Estienne, M., Kean, R., Porta, A., Tain, J. L., Sidelnik, I., Anderson, T., Askins, M., Bagdasarian, Z., Baldoni, A., Barna, A., Benson, T., Bergevin, M., Bernstein, A., Birrittella, B., Bogetic, S., Boissevain, J., Borusinki, J., Boyd, S., Brooks, T., Budsworth, Mat, Burns, J., Calle, M., Camilo, C., Carroll, A., Coleman, J., Collins, R., Connor, C., Cowen, D., Crow, B., Curry, J., Dalnoki-Veress, F., Danielson, D., Diwan, M., Dixon, S., Drakopoulou, L., Duron, J., Dye, S., Fargher, S., Fienberg, A., Fischer, V., Foster, R., Frankiewicz, Kat, Gamble, T., Gooding, D., Gokhale, S., Gregorio, R., Gribble, J., Griskevich, J., Hadley, D., He, J., Healey, K., Hecla, J., Holt, G., Jabbari, C., Jewkes, K., Kaiser, R., Keenan, M., Keener, P., Kneale, Liz, Kudryavtsev, V., Kunkle, P., Litchfield, P., Liu, X. Ran, Lynch, G., Malek, M., Marr-Laundrie, P., Masic, B., Mauger, C., Mccauley, N., Metelko, C., Mills, R., Mitra, A., Muheim, F., Mullen, A., Murphy, A., Needham, M., Neights, E., Ogren, K., Orebi Gann, G., Oxborough, L., Paling, S., Papatyi, A., Paulos, B., Pershing, T., Pickard, L., Quillin, S., Resoro, R., Richards, B., Sabarots, L., Scarff, A., Schnellbach, Yan-Jie, Scovell, P., Seitz, B., Shea, O., Shebalin, V., Smith, G., Smy, M., Song, H., Spooner, N., Stanton, C., Stone, O., Svoboda, R., Szoldos, S., Thompson, L., Thomson, F., Toth, C., Vagins, M., Berg, Rick, Ventura, S., Walsh, B., Webster, J., Weiss, M., Westphal, D., Wetstein, M., Wilson, T., Wilson, S., Wolcott, S., Wright, M., Berryman, J. M., Collar, J. I., Erlandson, A., Gariazzo, S., Garzelli, M. V., Giunti, C., Goldblum, B. L., Hayes, A., Hedges, S., Mariani, C., Minic, D., Mougeot, X., Naim, D., Newby, J., Ni, K., O Donnell, T., Ozturk, S., Périssé, L., Pestes, R., Sonzogni, A. A., Tabrizi, Z., Vivier, M., Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Neutrino de Champagne Ardenne (LNCA - UMS 3263), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique subatomique et des technologies associées (SUBATECH), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Cryogénie (NEEL - Cryo), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Hélium : du fondamental aux applications (NEEL - HELFA), Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut Laue-Langevin (ILL), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département de Physique Nucléaire (ex SPhN) (DPHN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, CHANDLER, CONNIE, CONUS, Daya Bay, JUNO, MTAS, NEOS, NuLat, PROSPECT, RENO, Ricochet, ROADSTR Near-Field Working Group, SoLid, Stereo, Valencia-Nantes TAGS, vIOLETA, WATCHMAN, and HEP, INSPIRE

Subjects
High Energy Physics - Experiment (hep-ex), [PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex], hep-ex, neutrino: energy spectrum, antineutrino: nuclear reactor, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], FOS: Physical sciences, neutrino: oscillation, neutrino: nuclear reactor, Particle Physics - Experiment, neutrino: flux, High Energy Physics - Experiment
Abstract

Nuclear reactors are uniquely powerful, abundant, and flavor-pure sources of antineutrinos that continue to play a vital role in the US neutrino physics program. The US reactor antineutrino physics community is a diverse interest group encompassing many detection technologies and many particle physics topics, including Standard Model and short-baseline oscillations, BSM physics searches, and reactor flux and spectrum modeling. The community's aims offer strong complimentary with numerous aspects of the wider US neutrino program and have direct relevance to most of the topical sub-groups composing the Snowmass 2021 Neutrino Frontier. Reactor neutrino experiments also have a direct societal impact and have become a strong workforce and technology development pipeline for DOE National Laboratories and universities. This white paper, prepared as a submission to the Snowmass 2021 community organizing exercise, will survey the state of the reactor antineutrino physics field and summarize the ways in which current and future reactor antineutrino experiments can play a critical role in advancing the field of particle physics in the next decade., Contribution to Snowmass 2021

Published
2022

16. Calculation of stress intensity factors in an isotropic multicracked plate: Part 2: Symbolic/numeric implementation

Author

Arnold, S. M, Binienda, W. K, Tan, H. Q, and Xu, M. H

Subjects
Structural Mechanics
Abstract

Analytical derivations of stress intensity factors (SIF's) of a multicracked plate can be complex and tedious. Recent advances, however, in intelligent application of symbolic computation can overcome these difficulties and provide the means to rigorously and efficiently analyze this class of problems. Here, the symbolic algorithm required to implement the methodology described in Part 1 is presented. The special problem-oriented symbolic functions to derive the fundamental kernels are described, and the associated automatically generated FORTRAN subroutines are given. As a result, a symbolic/FORTRAN package named SYMFRAC, capable of providing accurate SIF's at each crack tip, was developed and validated. Simple illustrative examples using SYMFRAC show the potential of the present approach for predicting the macrocrack propagation path due to existing microcracks in the vicinity of a macrocrack tip, when the influence of the microcrack's location, orientation, size, and interaction are taken into account.

Published
1992

17. A fully encapsulated piezoelectric--triboelectric hybrid nanogenerator for energy harvesting from biomechanical and environmental sources.

Author

Chen, C. Y., Tsai, C. Y., Xu, M. H., Wu, C. T., Huang, C. Y., Lee, T. H., and Fuh, Y. K.

Subjects
PIEZOELECTRIC actuators, ACTUATORS, ELECTRIC actuators, PIEZOELECTRIC devices, TRIBOELECTRICITY
Abstract

In this paper, a hybrid nanogenerator with concurrently harvested piezoelectric and triboelectric mechanisms, called a fully encapsulated piezoelectric--triboelectric hybrid nanogenerator (PTHG), is demonstrated. In the construction of piezoelectric nanogenerator (PENG), an in-situ poling near-field electrospinning (NFES) was utilized to direct-write piezoelectric polymeric nano/micro fibers (NMFs) polyvinylidene fluoride (PVDF) as the functional layer of piezoelectric nanogenerators. On the other hand, the nano-textured functional layer of triboelectric nanogenerators (TENGs) is also concurrently combined with PENG. This hybridized nanogenerator was demonstrated to simultaneously harvest piezoelectric and triboelectric output such that the superimposed peak output voltage /current signals of ~130 V/4 µA at 2 Hz, which can be translated to the area power density of 8.34 mW/m2. Individually measured TENG under a hand-induced strain 0.2 and 2 Hz actuation, the output voltage/current peak is measured about 110 V/2.8 µA, while the PENG counterpart shows the the output voltage/current peak is about 18 V/0.6 µA. In addition, the proposed PTHG can harvest sustainable energy sources such as rain water with the output maximum voltage reaches ~20 V and area power density ~0.981 mW/m² for dropping rate of 10 ml/s. This research shows the substantial improvement in the synergy of nano-textured triboelectric and piezoelectric functional layers. The practical application of the self-powered system can be ubiquitously implemented in the sustainable energy sources and future industry 4.0 scenarios to provide the stand alone energy sources of IoT sensors. [ABSTRACT FROM AUTHOR]

Published
2019
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18. Study of x-ray emission enhancement via high contrast femtosecond laser interacting with solid foil

Author

Chen, L. M., Kando, M., Bulanov, S. V., Koga, J., Nakajima, K., Tajima, T., Xu, M. H., Yuan, X. H., Li, Y. T., Dong, Q. L., and Zhang, J.

Subjects
Plasma Physics (physics.plasm-ph), FOS: Physical sciences, Physics - Plasma Physics
Abstract

We studied the hard x-ray emission and the K-alpha x-ray conversion efficiency produced by 60 fs high contrast frequency doubled Ti: sapphire laser pulse focused on Cu foil target. Cu K-alpha photon emission obtained with second harmonic laser pulse is more intense than the case of fundamental laser pulse. The Cu K-alpha conversion efficiency shows strong dependence on laser nonlinearly skewed pulse shape and reaches the maximum value 4x10-4 with 100 fs negatively skewed pulse. It shows the electron spectrum shaping contribute to the increase of conversion efficiency. Particle-in-cell simulations demonstrates that the application of high contrast laser pulses will be an effective method to optimize the x-ray emission, via the Enhanced Vacuum Heating mechanism., 16 pages, 4 figures, presented in 2006 APS March Meeting, Baltimore, MD. Session N43: Quantum Optics and Strong Field Physics, Abstract: N43.00011

Published
2006

19. Surface acoustic waves in acoustic superlattice lithium niobate coated with a waveguide layer.

Author

Yang, G. Y., Du, J. K., Huang, B., Jin, Y. A., and Xu, M. H.

Subjects
WAVEGUIDES, ACOUSTIC surface waves, LITHIUM niobate
Abstract

The effects of the waveguide layer on the band structure of Rayleigh waves are studied in this work based on a one-dimensional acoustic superlattice lithium niobate substrate coated with a waveguide layer. The present phononic structure is formed by the periodic domain-inverted single crystal that is the Z-cut lithium niobate substrate with a waveguide layer on the upper surface. The plane wave expansion method (PWE) is adopted to determine the band gap behavior of the phononic structure and validated by the finite element method (FEM). The FEM is also used to investigate the transmission of Rayleigh waves in the phononic structure with the interdigital transducers by means of the commercial package COMSOL. The results show that, although there is a homogeneous waveguide layer on the surface, the band gap of Rayleigh waves still exist. It is also found that increasing the thickness of the waveguide layer, the band width narrows and the band structure shifts to lower frequency. The present approach can be taken as an efficient tool in designing of phononic structures with waveguide layer. [ABSTRACT FROM AUTHOR]

Published
2017
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20. A new LQP alternating direction method for solving variational inequality problems with separable structure.

Author

Bnouhachem, Abdellah, Hamdi, Abdelouahed, and Xu, M. H.

Subjects
MATHEMATICAL inequalities, LOGARITHMIC functions, QUADRATIC forms, PROBLEM solving, CONVEX programming
Abstract

We presented a new logarithmic-quadratic proximal alternating direction scheme for the separable constrained convex programming problem. The predictor is obtained by solving series of related systems of non-linear equations in a parallel wise. The new iterate is obtained by searching the optimal step size along a new descent direction. The new direction is obtained by the linear combination of two descent directions. Global convergence of the proposed method is proved under certain assumptions. We show theO(1 / t) convergence rate for the parallel LQP alternating direction method. [ABSTRACT FROM PUBLISHER]

Published
2016
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21. Exchange bias in LiNi0.5Mn1.5O4-NiO nanocomposites.

Author

Xu, M. H., Wang, Z. H., Liu, L. Z., Yang, Q., Yu, Z. A., Shen, L. J., Zhong, W., and Du, Y. W.

Subjects
*NANOCOMPOSITE materials, *MAGNETIC properties, *SCANNING electron microscopy, *TRANSMISSION electron microscopy, *FERROMAGNETIC materials, *FERROMAGNETISM, *ANTIFERROMAGNETIC materials
Abstract

Composites LiNi0.5Mn1.5O4-NiO nanosticks were prepared by a simple molten salt route of adding MnSO4 to molten LiNO3, NaNO3 and slightly excess NiSO4·6H2O. Field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) investigations revealed that one-dimensional composites LiNi0.5Mn1.5O4-NiO nanosticks were generated in a large quantity. The result of dc and ac magnetisation, as well as magnetic hysteresis measurements, shows that three different magnetic phases, i.e. ferrimagnetic, antiferromagnetic (AFM) and spin-glass-like (SGL) phases may coexist in LiNi0.5Mn1.5O4-NiO nanocomposites. Furthermore, magnetic measurements suggest that the exchange bias (EB) effect was obtained at low temperature. [ABSTRACT FROM AUTHOR]

Published
2015
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22. Effects of laser prepulse on proton generation: active manipulation of the distribution of laser accelerated proton beams.

Author

Batani, D., Redaelli, R., Dezulian, R., Lundh, O., Lindau, F., Persson, A., Osvay, K., Wahlström, C.-G., Carroll, D. C., McKenna, P., Bandyopadhyay, S., Pepler, D., Neely, D., Kar, S., Simpson, P. T., Markey, K., Zepf, M., Xu, M. H., and Li, Y. T.

Subjects
PROTON beams, LASER beams, LASERS, PROTONS, SHOCK wave diffraction
Abstract

Laser pre-pulse is a major issue in experiments on laser-generation of protons, often limiting the performances of laser sources. In this paper, we show how we can actively use a low intensity prepulse (<1013 W/cm2, ns duration) to manipulate the proton beam direction or spatial energy distribution. The prepulse is focused onto the front surface of a thin foil before the arrival of the high intensity pulse (≈1019 W/cm2, ps duration). Under oblique high-intensity irradiation and for low prepulse intensities, the proton beam is directed away from the target normal. Deviation is towards the laser forward direction, with an angle that increases with the level and duration of the ASE pedestal. Also, for a given laser pulse, beam deviation increases with proton energy. The observations are discussed in terms of Target Normal Sheath Acceleration, in combination with a laser-controllable shock wave locally deforming the target surface. Results obtained with an annular intensity distribution of the prepulse show smooth proton beams with a sharp circular boundary at all energies. Potential mechanisms to explain the observations are discussed. [ABSTRACT FROM AUTHOR]

Published
2008
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23. Enhancement and Spatial Characteristics of Kα X-ray Emission from High-contrast Relativistic fs Laser Plasmas.

Author

Chen, L. M., Kando, M., Kotaki, H., Nakajima, K., Bulanov, S. V., Tajima, T., Xu, M. H., Li, Y. T., Dong, Q. L., and Zhang, J.

Abstract

We studied the hard X-ray emission and the Kα X-ray conversion efficiency (ηK) produced by 70 fs, 400 nm high-contrast femtosecond laser pulse focused on Cu solid target. At an intensity I = 2 × 1018 W · cm−2, the Cu ηK can reach 1 × 10−4. Compared with the Cu ηK obtained by using a 800-nm low-contrast laser pulse, the second harmonic exhibits a higher X-ray flux by a factor of 2. We show that the use of high-contrast laser pulses may be an effective method to optimize the Kα X-ray emission via the vacuum heating mechanism. In addition, the laser focusing was varied widely to give a range of intensities from 1015–1018 W · cm−2 by target offset from best laser focus. Two individual emission peaks are obtained, one is at best focal spot and the other is at larger target offset corresponding to ∼1015 W · cm−2. Each X-ray emission peak is corresponding to different energy absorption mechanism. [ABSTRACT FROM AUTHOR]

Published
2007
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24. Relativistic Laser Acceleration Of Electrons Along Solid Surfaces.

Author

Sheng, Z. M., Li, Y. T., Chen, M., Ma, Y. Y., Yuan, X. H., Xu, M. H., Zheng, Z. Y., Liang, W. X., Yu, Q. Z., Zhang, Y., Liu, F., Wang, Z. H., Wei, Z. Y., Jin, Z., Zhang, J., Nakamura, T., and Mima, K.

Subjects
SOLID-state lasers, ACCELERATION (Mechanics), SURFACES of solids, ELECTRON emission, ELECTRON beams, CONES, THERMODYNAMICS, ULTRASHORT laser pulses, MAGNETIC fields
Abstract

Recent experimental and theoretical studies on surface electron emission will be presented. A collimated fast electron beam was observed along the target surface irradiated by intense laser pulses up to 20TW when the laser is incident with large angles such as over 45 degree. Numerical simulations suggest that such an electron beam is formed due to the confinement of the surface quasistatic electric and magnetic fields. Meanwhile, an acceleration process similar to the inverse-free-electron-laser is found to occur and is responsible for the generation of the most energetic electrons. A general formula for electron angular distributions accounting for the quasistatic electric and magnetic fields is given. In certain conditions, quasi-monoenergetic electron beams are also produced. These results are of interest for potential applications of laser-produced electron beams and helpful to the undersanding of the cone-target physics in the fast ignition related experiments. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2006
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25. Frequency bandwidth optimization of photothermal technique for thermal conductivity depth profiling.

Author

Xu, M. H., Cheng, J. C., and Zhang, S. Y.

Subjects
*VIBRATION (Mechanics), *HEAT
Abstract

The frequency bandwidth of photothermal technique for thermal conductivity depth profiling has been studied, which is based on an iterative numerical algorithm for inverse calculation of inhomogeneous thermal conductivity depth profiles of solid samples. This inversion algorithm should require a sufficient frequency bandwidth since the numerical experiments have demonstrated that systematic errors will occur in the inversion from insufficient data. According to the thermal wave propagation property, at low frequency range, the thermal wave can penetrate into deep region of the sample, but it will depress spatial resolution because of its long thermal wavelength. Nevertheless, lack of low frequency the detected information will cause the derivation of the depth profiling in the deep part. On the other hand, with high frequency, the thermal wave only can penetrate into shallow regions near the surface of the sample, although the spatial resolution will be intensified because of its short thermal wavelength. However, lack of high frequency information will induce the depth profiling derivation near the surface layer. Theoretical analyses have indicated that there is a high frequency f[sub high], at which or over the amplitude of the surface temperature tends to be proportional inversely to square root of frequency f, but the phase tends to a constant 0.25π. Besides, there is a low frequency f[sub low], at which or below the amplitude will tend to be inversely proportional to f and the phase will tend to a constant 0.5π under the heat-insulation boundary condition at the rear surface. With the frequency bandwidth (f[sub low],f[sub high]) all the necessary information is essentially included for reconstructing the depth profiling. Practically, the numerical experiments have also demonstrated the frequency bandwidth can be less than (f[sub low],f[sub high]) based on the investigated conditions, which will be described in detail in the paper. © 200... [ABSTRACT FROM AUTHOR]

Published
2000

26. Angle-dependent modulated spectral peaks of proton beams generated in ultrashort intense laser-solid interactions.

Author

Su, L. N., Hu, Z. D., Zheng, Y., Liu, M., Li, Y. T., Wang, W. M., Sheng, Z. M., Yuan, X. H., Xu, M. H., Shen, Z. W., Fan, H. T., Chen, L. M., Lu, X., Ma, J. L., Wang, X., Wang, Z. H., Wei, Z. Y., and Zhang, J.

Subjects
ELECTRONIC modulation, PROTON beams, ULTRASHORT laser pulses, ALUMINUM foil, SPECTROMETERS
Abstract

Proton acceleration from 4 im thick aluminum foils irradiated by 30-TW Ti:sapphire laser pulses is investigated using an angle-resolved proton energy spectrometer. We find that a modulated spectral peak at ~0.82 MeV is presented at 2.5° off the target normal direction. The divergence angle of the modulated zone is 3.8°. Two-dimensional particle-in-cell simulations reveal that self-generated toroidal magnetic field at the rear surface of the target foil is responsible for the modulated spectral feature. The field deflects the low energy protons, resulting in the modulated energy spectrum with certain peaks. [ABSTRACT FROM AUTHOR]

Published
2014
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28. A new concept of the International Celestial Reference Frame: the epoch ICRF.

Author

Xu, M. H., Wang, G. L., and Zhao, M.

Subjects
*CELESTIAL reference systems, *APPROXIMATION theory, *ASTROMETRY, *VERY long baseline interferometry, *STELLAR evolution
Abstract

The epoch International Celestial Reference Frame (epoch ICRF) is proposed as a new concept in order to consider the effect of apparent proper motion of the position of a radio source due to acceleration of the spatial origin of the ICRF, the centre of mass of the Solar system. This apparent proper motion has a magnitude of approximately 5.8 microarcsec (μas) per year, and for the 30-year very long baseline interferometry (VLBI) observational history these position variations will exceed 100 µas. We show that the dipole structure of the apparent proper motions leads to global rotation in the ICRF2 and the main term, the shift of direction of the origin of right ascension, reaches 25 µas per century. The 'epoch ICRF' is constructed using epoch positions at J2000.0 and apparent proper motions of radio sources, which are reported here for 295 ICRF2-defining sources. [ABSTRACT FROM AUTHOR]

Published
2013
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29. A Permanent Magnet Brushless DC Motor With Bifilar Winding for Automotive Engine Cooling Application.

Author

Cui, Wei, Gong, Yu, and Xu, M. H.

Subjects
PERMANENT magnets, DIRECT current electric motors, ELECTRIC windings, AUTOMOBILE engines, COOLING, SIMULATION methods & models, CASCADE converters
Abstract

This paper presents a sensorless bifilar wound permanent magnet brushless DC (BW-PMBLDC) motor fan for automotive engine cooling applications. The key is to incorporate the bifilar winding design into the conventional half-wave PMBLDC motor. Due to the perfect flux-coupling effect between bifilar winding, a regenerative capability is developed so that the trapped energy in the conducting winding during the turn-off period can be re-dumped to DC source through the other winding in the bifilar pair, hence effectively promoting the energy efficiency and repressing the voltage spikes. Moreover, the complementary scheme developed between the bifilar wound phases enables bipolar excitation on the unipolar converter topology. Therefore, the BWPMBLDC motor cannot only offer the advantages of full-wave motor in efficiency, voltage spike reduction, and low torque ripple, but also retain the advantages of simplicity and robustness of unipolar converter topology. Both simulation and experimental results are presented to validate the feasibility. [ABSTRACT FROM AUTHOR]

Published
2012
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30. The solar acceleration obtained by VLBI observations.

Author

Xu, M. H., Wang, G. L., and Zhao, M.

Subjects
*ASTRONOMICAL observations, *MILKY Way, *GEODETIC astronomy, *SOLAR system, SOLAR evolution
Abstract

Aims. The three-dimensional acceleration vector of the solar system barycenter was estimated from VLBI delay observations. We also provide a first physical explanation for this acceleration vector. Methods. Two methods for the acceleration estimation were developed in the analysis of the global astrometric/geodetic VLBI observations. One is to take the solar acceleration vector as a global parameter that is to be directly estimated. The second method is to obtain the acceleration by fitting the solar velocity variation time series produced from the VLBI data analysis. Results. The results of these two methods are consistent with each other within their uncertainties. The acceleration vector derived from the first method is (7.47 ± 0.46, 0.17 ± 0.57, 3.95 ± 0.47) mm s-1 yr-1 in the Galactic Cartesian coordinate system. Conclusions. The Galactocentric component of the solar acceleration we obtained agrees well with the predicted value from the rotation movement of the Sun and has a high accuracy. The detected strong vertical component perpendicular to the Galactic plane may be important for the research of the Milky Way. [ABSTRACT FROM AUTHOR]

Published
2012
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31. Enhancement of ion generation in femtosecond ultraintense laser-foil interactions by defocusing.

Author

Xu, M. H., Li, Y. T., Carroll, D. C., Foster, P. S., Hawkes, S., Kar, S., Liu, F., Markey, K., McKenna, P., Streeter, M. J. V., Spindloe, C., Sheng, Z. M., Wahlström, C.-G., Zepf, M., Zheng, J., Zhang, J., and Neely, D.

Subjects
*FEMTOSECOND lasers research, *PROTON beams, *ULTRASHORT laser pulses, *PROTONS, *IONS
Abstract

A simple method to enhance ion generation with femtosecond ultraintense lasers is demonstrated experimentally by defocusing laser beams on target surface. When the laser is optimally defocused, we find that the population of medium and low energy protons from ultra-thin foils is increased significantly while the proton cutoff energy is almost unchanged. In this way, the total proton yield can be enhanced by more than 1 order, even though the peak laser intensity drops. The depression of the amplified spontaneous emission (ASE) effect and the population increase of moderate-energy electrons are believed to be the main reasons for the effective enhancement. [ABSTRACT FROM AUTHOR]

Published
2012
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32. Solving the Matrix Nearness Problem in the Maximum Norm by Applying a Projection and Contraction Method.

Author

Xu, M. H. and Shao, H.

Subjects
PROBLEM solving, MATRICES (Mathematics), VARIATIONAL inequalities (Mathematics), CONVEX sets, NUMERICAL analysis, ALGORITHMS
Abstract

Let S be a closed convex set of matrices and C be a given matrix. The matrix nearness problem considered in this paper is to find a matrix X in the set S at which max {∣xij - cij ∣} reaches its minimum value. In order to solve the matrix nearness problem, the problem is reformulated to a min-max problem firstly, then the relationship between the min-max problem and a monotone linear variational inequality (LVI) is built. Since the matrix in the LVI problem has a special structure, a projection and contraction method is suggested to solve this LVI problem. Moreover, some implementing details of the method are presented in this paper. Finally, preliminary numerical results are reported, which show that this simple algorithm is promising for this matrix nearness problem. [ABSTRACT FROM AUTHOR]

Published
2012
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33. Spectral modification of laser-accelerated proton beams by self-generated magnetic fields.

Author

Robinson, A. P. L., Foster, P., Adams, D., Carroll, D. C., Dromey, B., Hawkes, S., Kar, S., Li, Y. T., Markey, K., McKenna, P., Spindloe, C., Streeter, M., Wahlström, C.-G., Xu, M. H., Zepf, M., and Neely, D.

Subjects
LASER beams, SPECTRUM analysis, MATHEMATICAL models, MAGNETIC fields, PROTON-proton interactions, SCIENTIFIC experimentation
Abstract

Target normal measurements of proton energy spectra from ultrathin (50-200 nm) planar foil targets irradiated by 1019Wcm-2 40 fs laser pulses exhibit broad maxima that are not present in the energy spectra from micron thickness targets (6μm). The proton flux in the peak is considerably greater than the proton flux observed in the same energy range in thicker targets. Numerical modelling of the experiment indicates that this spectral modification in thin targets is caused by magnetic fields that grow at the rear of the target during the laser-target interaction. [ABSTRACT FROM AUTHOR]

Published
2009
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38. Multipeak emission of the fast electron beams along the target surface in ultrashort laser interaction with solid targets.

Author

Yuan, X. H., Li, Y. T., Xu, M. H., Zheng, Z. Y., Chen, M., Liang, W. X., Yu, Q. Z., Zhang, Y., Liu, F., Bernhardt, J., Wang, S. J., Wang, Z. H., Wei, Z. Y., Zhao, W., and Zhang, J.

Subjects
ELECTRON beams, ELECTRON optics, CATHODE rays, ELECTROMAGNETIC fields, MAGNETIC fields
Abstract

The spatial and energy distributions of fast electrons emitted from foil targets irradiated by ultrashort intense laser pulses are measured. Four groups of collimated emissions of fast electrons along the front and rear target surfaces are observed for an incidence angle of <60°. This multipeak characterization is found to be independent of laser polarization states. Numerical simulations reveal that the electron beams are formed due to the deformation of the target surface and then guided by the induced quasistatic electromagnetic fields. [ABSTRACT FROM AUTHOR]

Published
2008
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39. Emission characteristics and chemical composition of PM10 from two coal fired power plants in China.

Author

Sui, J. C., Xu, M. H., Du, Y. G., Liu, Y., Yu, D. X., and Yi, G. Z.

Subjects
EMISSIONS (Air pollution), COAL, BOILERS, MICROSTRUCTURE, POWER plants
Abstract

By using low pressure impactor, fly ash was sampled in the entrance and exit of the dust cleaning equipments, such as ESP and venturi scrubber, in a 50 and 100 MW utility boiler. The composition, mass size distribution and microstructure of fly ash were measured. A similar bimodal distribution of PM10 was obtained in the studied boilers. The small and large modes are formed at 01 and 40 μm respectively. Based on the comparison of concentrations of Si and Al in the size segregated ash, it is concluded that the ash with size smaller than 0377 μm is formed by the nucleation of vaporised mineral components and growth via coagulation and heterogeneous condensation. The results by microstructure measurements showed that the typical microstructure of submicron and coarse PM is spherical, except for a few irregular particles in shape. The collection efficiency of the dust cleaning equipments had a minimum in particle size range of 001–1 μm. [ABSTRACT FROM AUTHOR]

Published
2007
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40. Emission characteristics and elemental partitioning of submicron particulate matter during combustion of pulverised bituminous coal.

Author

Sui, J. C., Xu, M. H., Du, Y. G., Liu, Y., and Yin, G. Z.

Subjects
EMISSIONS (Air pollution), PARTICULATE matter, BITUMINOUS coal, FURNACES, FLY ash, COMBUSTION, SCANNING electron microscopy, TEMPERATURE
Abstract

Laboratory scale experiments were conducted to study the emission characteristics and elemental partition of submicron particulate matter (PM) burning Pingdingshan bituminous coal in a drop tube furnace (DTF). Factors influencing the emission characteristics and elemental partition of the submicron PM were investigated, which include the distribution of furnace temperature, coal particle size and oxygen concentration. The fly ash smaller than 10 μm (PM10) in the combustion products was collected by a low pressure impactor (LPI) to obtain size segregated ash samples, and the larger ash particles were collected by a cyclone before the impactor. A similar bimodal distribution of ash particles with a small and a large mode at 0·1 and 4·3 μm respectively, was obtained in all runs. Based on the comparison of concentrations of ash forming elements in the size segregated ash, it was concluded that the ash smaller than 0·4 μm was formed by the nucleation and growth of vaporised ash components. The microstructure of submicron PM was measured by a scanning electron microscopy (SEM). Coal particle size, oxygen concentration, and especially temperature affect submicron PM emission significantly in the combustion. Increasing temperature and oxygen concentration, and decreasing coal particle size leads to more submicron PM formation. With increasing temperature and oxygen concentration, the fractions of Si, Fe, Cu, Zn and Pb in submicron PM increase by 2–3·5 times, the fractions of Mg and Ca show a moderate increase, but Al and Mn appear to be nearly unchanged. It is also found that the coal particle size has little influence on the elemental partition of submicron PM. [ABSTRACT FROM AUTHOR]

Published
2007
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41. Effects of shock waves on spatial distribution of proton beams in ultrashort laser-foil interactions.

Author

Xu, M. H., Li, Y. T., Yuan, X. H., Yu, Q. Z., Wang, S. J., Zhao, W., Wen, X. L., Wang, G. C., Jiao, C. Y., He, Y. L., Zhang, S. G., Wang, X. X., Huang, W. Z., Gu, Y. Q., and Zhang, J.

Subjects
*PROTON beams, *SHOCK waves, *ULTRASHORT laser pulses, *HYDRODYNAMICS, *PLASMA lasers, *ELECTRIC fields, *ION bombardment, *METAL foils
Abstract

The characteristics of proton beam generated in the interaction of an ultrashort laser pulse with a large prepulse with solid foils are experimentally investigated. It is found that the proton beam emitted from the rear surface is not well collimated, and a “ring-like” structure with some “burst-like” angular modulation is presented in the spatial distribution. The divergence of the proton beam reduces significantly when the laser intensity is decreased. The “burst-like” modulation gradually fades out for the thicker target. It is believed that the large divergence angle and the modulated ring structure are caused by the shock wave induced by the large laser prepulse. A one-dimensional hydrodynamic code, MED103, is used to simulate the behavior of the shock wave produced by the prepulse. The simulation indicates that the rear surface of the foil target is significantly modified by the shock wave, consequently resulting in the experimental observations. [ABSTRACT FROM AUTHOR]

Published
2006
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50. Propagation of a short-pulse laser-driven electron beam in matter.

Author

Volpe, L., Batani, D., Birindelli, G., Morace, A., Carpeggiani, P., Xu, M. H., Liu, F., Zhang, Y., Zhang, Z., Lin, X. X., Wang, S. J., Zhu, P. F., Meng, L. M., Wang, Z. H., Li, Y. T., Sheng, Z. M., Wei, Z. Y., Zhang, J., Santos, J. J., and Spindloe, C.

Subjects
CATHODE rays, ELECTRONS, ELECTRIC conductivity, ELECTRON beams, GEOMETRY
Abstract

We studied the transport of an intense electron beam produced by high intensity laser pulses through metals and insulators. Targets were irradiated at two different intensities, 1017 W/cm2 and 1019 W/cm2, at the laser facility Xtreme Light XL-III in Beijing, a Ti:Sa laser source emitting 40 fs pulses at 800 nm. The main diagnostic was Cu-Kα fluorescence imaging. Images of Kα spots have been collected for those two laser intensities, for different target thickness, and for different materials. Experimental results are analyzed taking into account both collisional and collective effects as well as refluxing at the edge of the target. The target temperature is evaluated to be Tc ∼ 6 eV for intensity I = 1017 W/cm2 (for all the tested materials: plastic, aluminium, and copper), and Tc ∼ 60 eV in aluminium and 120 eV in titanium for intensity I = 1019 W/cm2. [ABSTRACT FROM AUTHOR]

Published
2013
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